Bi-fuel engines are capable of operating on two different fuel types, i.e., a first fuel type and a second fuel type. Typically, the first fuel type includes either gasoline or diesel fuel, and the second fuel type includes an alternative fuel, such as but not limited to Compressed Natural Gas (CNG), Liquefied Petroleum Gas (LPG) or hydrogen. The two different fuels are stored in separate tanks, and the bi-fuel engine may run on one fuel at a time, or may alternatively run on a combination of the first fuel type and the second fuel type.
Some bi-fuel engines utilize a direct injection assembly having a high pressure pump that is directly attached to the engine for increasing the pressure of the first fuel type, e.g., gasoline, which is then injected directly into the combustion chambers of the engine. When the bi-fuel engine is operating on the second fuel type, the first fuel type remains stagnant within its fuel supply system. As such, the fuel disposed within the direct injection assembly directly adjacent the bi-fuel engine, and particularly the high pressure pump, becomes heated. Overheating of the first fuel type may cause vaporization of the first fuel type within the direct injection assembly.